Vemurafenib is a type of cancer treatment called a cancer growth blocker. Vemurafenib is given for melanomas that have a change (mutation) in a gene called BRAF. The change in this gene leads to the production of a changed (mutated) BRAF protein. This protein helps melanoma tumours grow.

Vemurafenib blocks (inhibits) the changed BRAF protein, which can stop the melanoma cells from growing and dividing.

Doctors can find out if your melanoma has a mutation in the BRAF gene. They do this by testing a piece of melanoma that has been removed during tests to diagnose the melanoma or during surgery.

The National Institute for Health and Care Excellence (NICE) gives advice on which drugs or treatments should be available on the NHS in England and Wales. It recommends that vemurafenib is available on the NHS in England and Wales. In Northern Ireland, the Health and Social Care Board (HSCB) has accepted the NICE decision recommending vemurafenib.

The Scottish Medicines Consortium (SMC) advises on the use of drugs within the NHS in Scotland. It recommends that vemurafenib is available on the NHS as a first treatment for melanoma that has spread to other parts of the body or can’t be removed by surgery.

Vemurafenib is taken twice a day, with doses 12 hours apart. You will usually take four vemurafenib tablets in the morning and four more 12 hours later. You can take vemurafenib with or without food, but you should not take it regularly on an empty stomach.

Always take your tablets exactly as your nurse or pharmacist explained. This is important to make sure they work as well as possible for you.

There are some important things to remember when taking your tablets:

If you forget to take your tablets and the next dose is due in less than four hours, just take your next dose at the usual time. Don’t take a double dose.

If you forget to take your tablets and the next dose is due in more than four hours, take your tablets as soon as you remember.

If you are sick after taking your tablets, just take your next dose at the usual time.

Keep the tablets in the original packaging and store them at room temperature away from heat and direct sunlight.

Keep the tablets in a safe place, out of the reach of children.

Get a new prescription before you run out of tablets and make sure you have plenty for holidays.

Return any tablets you have to the pharmacist if your treatment is stopped. Don’t flush them down the toilet or throw them away.

You usually take vemurafenib for as long as it controls the melanoma. Rarely, vemurafenib may be stopped or the dose reduced if it causes severe side effects.

We explain the most common side effects of vemurafenib here. But we don’t include all the less common ones that are unlikely to affect you. You may get some of the side effects we mention, but you are very unlikely to get all of them.

Always tell your doctor, nurse or pharmacist about the side effects you have. They can prescribe drugs to help control them and give you advice about managing them.

Skin changes

Some mild skin changes are common with vemurafenib. You may notice your skin is itchy, dry or scaly, or warts develop. You should tell your specialist nurse or doctor if you develop any of these changes as they can prescribe creams and ointments to help.

If you notice a rash, or have blisters or peeling skin, tell your specialist nurse or doctor straight away.

Sensitivity to light

During treatment with vemurafenib, your skin will be more sensitive to sunlight (even on a cloudy day). When you’re outdoors, you should wear a sunscreen with a high sun protection factor (SPF) of at least 30. Re-apply this every 2–3 hours or as instructed. Some doctors and specialist nurses advise using a sunscreen with an SPF of 50, so check this with your hospital team. They’ll also advise you to put sunblock on your lips and to cover up with clothing and a hat.

Effects on the hands and/or feet

You may notice redness of the palms of your hands and soles of your feet. Sometimes, your hands and feet can become sore or swollen. There may also be changes in sensation, such as numbness or tingling. If you notice this, let your specialist nurse or doctor know.

Sometimes, if these side effects don’t settle or if blisters develop, your doctor may change the dose of vemurafenib.

Other skin cancers

Some people may develop other types of skin cancer (squamous cell or, less commonly, basal cell skin cancer) while taking vemurafenib. Usually, these are easily removed with surgery. You’ll be asked to check your skin regularly for signs of these cancers, such as a small lump or an area that looks scaly, bleeds or has a hard horny cap.

Your specialist nurse or doctor will tell you what to look out for and will also check your skin when you’re seen in clinic. If you notice anything unusual between clinic appointments, let your specialist nurse or doctor know.

Headaches

Vemurafenib can cause headaches. Let your doctor or nurse know if this happens, as they can give you painkillers for it.

Taste changes or loss of appetite

Some people notice that food tastes different or they lose their appetite while taking vemurafenib. This can be mild and may only last a few days. If it doesn’t improve, you can ask to see a dietitian or specialist nurse at your hospital. They can give you advice on coping with taste changes, improving your appetite, and keeping to a healthy weight.

Diarrhoea

Vemurafenib can cause frequent or loose bowel movements. Your doctor can prescribe drugs to help with this. Let your doctor now if it’s severe or doesn’t get better. It’s important to drink at least two litres (three and a half pints) of fluids every day if you have diarrhoea.

Constipation

You may get constipated. Drinking at least two litres (three and a half pints) of fluids every day will help. Try to eat more fibre (such as fruit, vegetables and wholemeal bread) and do some gentle exercise. You may need to take medicine (laxatives) to help with constipation. Your doctor can prescribe these or you can buy them at a pharmacy.

Feeling sick

If you feel sick, your doctor can prescribe anti-sickness (anti-emetic) drugs to prevent or reduce nausea or vomiting. If the drugs don’t help, tell your specialist nurse or doctor. They can change the anti-sickness drug to one that works better for you.

Tiredness (fatigue)

Feeling tired is a common side effect. Try to pace yourself and get as much rest as you need. Try to balance this with taking some gentle exercise, such as short walks, which will help. If you feel sleepy, don’t drive or operate machinery.

Effects on the hair

Your hair may become thinner while you’re taking vemurafenib. This includes body hair, eyelashes and eyebrows, as well as hair on your head. Changes to your hair are usually temporary and improve during or after stopping treatment. However, sometimes changes can be permanent. Some people may find that their hair has a different texture when it grows back.

Muscle and joint pain

You may have pain or stiffness in your back, joints or muscles. Your doctor can prescribe painkillers to help.

Fluid retention

You may put on weight or notice swelling around your eyes and ankles. This is caused by fluid building up. This isn’t harmful, but it can be upsetting and uncomfortable. Tell your doctor if this happens. You may be given diuretics (drugs that make you pass more urine) to help get rid of some of the fluid, or it may settle by itself.

Cough

Vemurafenib can sometimes cause a cough. If you notice this, let your doctor know so they can give you medicines to help.

Fever and chills

You may have a fever or chills when taking vemurafenib. Tell your specialist doctor or nurse if this happens.

Weakness in the face muscles

Vemurafenib can sometimes cause weakness or paralysis in one side of the face. This may cause your mouth to droop and it may be difficult to close the eye on the affected side of your face. The paralysis usually improves when you stop taking the drug.

Heart problems

You will have tests to see how well your heart is working before you start taking vemurafenib and during treatment. In a small number of people, vemurafenib can cause the heartbeat to become irregular or fast (sometimes known as palpitations). If you have palpitations or you feel faint, tell your doctor immediately.

Eye problems

You may have eye pain, swelling, redness or, less commonly, changes to your vision such as blurred vision. Let your specialist nurse or doctor know straight away if you develop any of these problems.

Allergic reaction

Vemurafenib can sometimes cause a serious allergic reaction. Signs may include swelling of the face, lips or tongue, a rash, dizziness or breathlessness. Contact the hospital straight away if you have any of these symptoms. Don’t take any more tablets until you have spoken to your specialist doctor or nurse.

Effects on the liver

Rarely, vemurafenib may cause changes in the way your liver works. Your doctor will monitor this closely by taking regular blood samples to check your liver is working properly.

It’s important to let your specialist nurse or doctor know if you feel unwell or have any side effects, even if they’re not mentioned above.

Other medicines

Some medicines, including those that you can buy in a shop or chemist, can be harmful to take when you’re having vemurafenib. Tell your cancer doctor about any medicines you’re taking, including over-the-counter drugs, complementary therapies and herbal drugs. You shouldn’t take any new medicines or over-the-counter drugs while you are taking vemurafenib without checking with your specialist nurse or doctor first.

Fertility

Doctors don’t yet know how vemurafenib may affect the fertility of men and women. It’s important to discuss fertility with your doctor before starting treatment.

Contraception

Your doctor will advise you not to become pregnant or father a child during and for six months after taking vemurafenib. Doctors do not know the effects of this drug on a developing baby.

Vemurafenib can affect how well some oral contraceptives work. Your doctor or nurse can talk to you about other forms of contraception.

Breastfeeding

Women are advised not to breastfeed during treatment and for a few months afterwards. This is in case there is any of the drug in their breast milk.

Medical and dental treatment

If you need to go to hospital for any reason other than cancer, always tell the doctors and nurses that you taking vemurafenib. Tell them the name of your cancer specialist so they can ask for advice.

This page has been compiled using information from a number of reliable sources, including the electronic Medicines Compendium (eMC; medicines.org.uk). If you’d like further information on the sources we use, please feel free to contact us.

This information was reviewed by a medical professional.

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